How to Calibrate a Digital Thermometer

Nick Davis

Available in a variety of models and sizes, digital thermometers measure temperature and outputs the measurement on a display similar to a calculator screen. The instruments are used in medical, food, human, industrial and other environments. Like there non-digital counterparts, you need to calibrate your digital thermometer to ensure it provides an accurate reading. Calibration is needed before using the thermometer for the first time; if you use the thermometer to measure both hot and cold temperatures; if you drop the thermometer; and if you use the digital thermometer multiple times during the same day.

Calibrate your digital thermometer using ice or hot water.

Calibrating – Using Ice

Step 1

Fill an insulated glass with crushed ice from a ice machine or by grinding ice cubes with a blender.

Step 2

Add 1/2 cup of water from a sink. Let the ice mixture sit for five minutes.

Step 3

Insert the sensing end of your digital thermometer into the center of the ice mixture. Push the thermometer to the middle of the glass.

Step 4

Let the digital thermometer sit in the ice mixture for 30 seconds. The thermometer should display 32 degrees F on its display.

If the thermometer reads “Error” or another temperature, repeat steps 3 and 4.

Step 5

Press the “Reset” button on the side of your thermometer. Your digital thermometer is now calibrated.

Calibrating – Using Boiling Water

Step 1

Fill a pot with 3 cups of water from a sink. Bring the water to a boil on a stove, burner or other heat source. Turn off the pot once the water is boiling.

Step 2

Insert the sensing end of your digital thermometer into the center of the hot water. Push the thermometer to the middle of the water.

Step 3

Let the digital thermometer sit in the water for 30 seconds. The thermometer should display 212 degrees F on its display, if you are at 1,000 feet elevation or less.

If the thermometer reads “Error” or another temperature, repeat steps 2 and 3.

Step 4

Press the “Reset” button on the side of your thermometer. Your digital thermometer is now calibrated.